Details

An updated kexec-tools package that fixes three security issues, variousbugs, and adds enhancements is now available for Red HatEnterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderatesecurity impact. Common Vulnerability Scoring System (CVSS) base scores,which give detailed severity ratings, are available for each vulnerabilityfrom the CVE links in the References section.

Kexec allows for booting a Linux kernel from the context of an alreadyrunning kernel.

Kdump used the SSH (Secure Shell) "StrictHostKeyChecking=no" option whendumping to SSH targets, causing the target kdump server's SSH host key notto be checked. This could make it easier for a man-in-the-middle attackeron the local network to impersonate the kdump SSH target server andpossibly gain access to sensitive information in the vmcore dumps.(CVE-2011-3588)

mkdumprd created initrd files with world-readable permissions. A local usercould possibly use this flaw to gain access to sensitive information, suchas the private SSH key used to authenticate to a remote server when kdumpwas configured to dump to an SSH target. (CVE-2011-3589)

mkdumprd included unneeded sensitive files (such as all files from the"/root/.ssh/" directory and the host's private SSH keys) in the resultinginitrd. This could lead to an information leak when initrd files werepreviously created with world-readable permissions. Note: With this update,only the SSH client configuration, known hosts files, and the SSH keyconfigured via the newly introduced sshkey option in "/etc/kdump.conf" areincluded in the initrd. The default is the key generated when running the"service kdump propagate" command, "/root/.ssh/kdump_id_rsa".(CVE-2011-3590)

Red Hat would like to thank Kevan Carstensen for reporting these issues.

This update also fixes several bugs and adds various enhancements.Space precludes documenting all of these changes in this advisory.Documentation for these bug fixes and enhancements will be availableshortly from the Technical Notes document, linked to in the Referencessection.

All kexec-tools users should upgrade to this updated package, whichcontains backported patches to resolve these issues and add theseenhancements.

Solution

Before applying this update, make sure all previously-released erratarelevant to your system have been applied.